The rolls to be moved are usually journaled with their respective trunnion or journal ends in holding elements or mounting pieces, i.e. bearing blocks, which, in turn, are arranged in guide pieces or bodies. The guide pieces are arranged at the sides of the respective windows or openings of the base or frame members, i.e. in cylinder blocks, or in pressure plates associated therewith, so as to be vertically movable.
German patent No. 24 40 495 describes a rolling mill with two working rolls, two intermediate rolls, and two support or backing rolls. Axial displacement of the intermediate rolls is carried out with hydraulic cylinders. The hydraulic cylinders can be provided in the base or frame member of the mill stand, and they are fixed, or movable in cylinder blocks of the base. This provides a compact assembly and arrangement.
However, because the hydraulic cylinders, when considering the arrangement in the base or in the cylinder block, are provided at a constant height, during shifting of the rolls one can not preclude moments which will impact in undesired manner on the bearing blocks. Accordingly, rather complex designs for the bearing blocks are required to prevent inappropriate stressing thereof, particularly moments which arise due to different positions of the holding elements or bearing blocks.
It was also found of disadvantage that the base or support members are weakened when making provision for mounting of the piston-and-cylinder units which effect the displacement, or to arrange the hydraulic piston-and-cylinder in the cylinder blocks. This, however, will mean that the provision of sufficiently powerful units for adjusting, bending or balancing, of the rolls will be made more difficult. Although one could make the cylinder blocks larger, this is generally not a desirable solution.